Tsetseris L, Kalfagiannis N, Logothetidis S, Pantelides ST. Role of N defects on thermally induced atomic-scale structural changes in transition-metal nitrides.
PHYSICAL REVIEW LETTERS 2007;
99:125503. [PMID:
17930516 DOI:
10.1103/physrevlett.99.125503]
[Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2007] [Indexed: 05/25/2023]
Abstract
Transition-metal nitrides (TMN) have exceptional stability, which underlies their use in various applications. Here, we study the role of N point defects on the stability of prototype TMNs using first-principles calculations. We find that distinct regimes for TMN changes relate to specific atomic-scale mechanisms, namely, diffusion of N interstitials (I(N)), of I(N) pairs, and of N vacancies. The activation of these processes occurs sequentially as the temperature is raised in a range of several hundreds of degrees, accounting for observed TMN changes under widely different conditions.
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